Core drill



Dec. 2U, 192 7.

R. WILCOX CORE DRILL Filed March 21, 1923 Patented Dec. 20, 192?.l

UNITED STATES PATE k:RALPH WILCOX, F CHICAGO, ILLINOIS, ASSIGNOR TO SULLIVAN MACHINERY COM- PANY, A CORPORATION 0F MASSACHUSETTS.

conn DRILL. y

Application led March 21, 1923. Serial No. 626,447.

My invention relates to core drills.

It hasl for its object to provide an improved core barrel. A further object is to provide such a core barrel having improved core holding means whereby the core may be retained in the core barrel during removal of the latter from the hole. A still further object of my invention is to provide an improved core barrel having improved l0 fluid passage means whereby the same is especially adapted to use with mud fluid.

A more specific object of my invention is to provide an improved core barrel especially adapted to use with mud fluid and to handle large cores, for example, such as those made in oil Well drilling, whereby the use of mud Huid is facilitated and wherebyV despite the weight of the core or despite the variation in ldiameter of the core which frequently occurs in soft formations, which ordinarily would result in the core slipping down through the core lifter, the core is effectually held in the core barrel in such manner as to eliminate the necessity'for fishing the same out from the bottom of the hole in an extra and time consuming operation after the elevation of the barrel. These and other advantages of my improved construction will, however, hereinafter more fully appear.

In the accompanying drawings I have shown two embodiments vwhich my invention may assume in practice.

In these drawings,

Fig.k 1 is a vertical sectional view of a portion of a core barrel equipped with my improvement.

Fig. 2 is a transverse sectional view on line 2 2 of Fig. 1.

Fig. 3 is a detail sectional view in general similar to'Fig. 1 and showing a modied construction.

In this illustrative construction I have shown an improved core barrel of the vMitchell type, generally indicated at 1, and comprising anvinternally and externally longitudinally luteddiamond carrying bit 2 threaded into a tapered shell and core lifter vsection 3 of reduced external diameter/and carrying a usual core lifter, herein in the form of a resilient split ring 4, this section 3 in turn being threaded onto an externally longitudinally fluted section 5 ofthe core barrel which is herein of improved construction and associated with improved core holding means hereinafter described.

More particularly referring to Fig. 1, it will be noted that the lower end 6 of the fluted section 5 which extends into the section 3 is bored concentrically with the bit and of substantially the same internal diameter as the bit and likewise provided with fluid passages therein, herein in the form of longitudinal flutes 7, corresponding to the fiutes in the inner periphery of the bit. Above this end portion 6, however, it will be noted that the section 5 is eccentrically bored as at 8 to provide a larger passage, whose circumference is at one point coincident with that of the bore in the portion 6 in such manner as to provide a proper core passage. As shown, this passage 8 is also provided with iiuid passages or longitudinally extending flutes 9 therein, certain of which form extensions of the flutes 7 in the end portion 6. By reason of the eccentric boring, it will be noted that a shoulder or ledge 10 is thus provided at the upper end of the end portion 6 which, as herein, preferably extends a substantial distance around the same, herein over half-way around the same. In my present construction, as preferably, I a-lso provide a' second and like eccentric bore 11 in the section 5 above the bore 8 and communicating therewith, which in turn produces a second shoulder or` ledge 12, similar to the shoulder or ledge 10 but preferably dierently located radially with respect to the ledge 10 and herein oppositely disposed with respect thereto. It will moreover be evident that if desired more than two eccentric bores may be provided, depending upon the particular conditions existing.

In the operation of my improved construction, where core conditions are favorable the core will be fed up through the barrel in the usual manner through the usual core passage which is provided coincident with the inner periphery .of the bit, the split ring core lifter I in its usual manner gripping and holding the core when it is broken oif from kthe bottom of the hole. In a usual construction, however, should the core for any reason, as for example a variation in diameter of the core such as is encountered in soft formations, slip through thecore lifter, the core would be left in the hole and require considerable time to be lost in fishingv it out. The same difficulty has been encountered with heavy cores and cores 0f the size necessary in oil well drilling which run from fourV to-siX inches indianister Yand consequently have ksilcligi'eat weicht.

that the core may be forced through friction grip of a usual core lifter. result of my improved construction including the eccentric bore ScrboiresS'andll and the shoulder or ledge 10 or shoulders or ledges l0' and12, it willV benoted` that When for any reason they core slips through the core lifter, a portionofl the core brings up against thev shoulder or ledge l0, or where, as preferably, 'aplurality of shoulders or ledges is provided. against one or the otherof-the shoulders or ledges in such manner-as toarrestits move-mentl and prevent loss` of the core. More particularly it Willvbe noted that duc to the arrangement ofthe ledgeson opposite sidesof the path of; the core, What may be called bailiev means-are provided for catching the latter onloneside-or the other, in suchinannei'- as to enable the'- core to be lifted and thus elfectually overcome the difficulties heretofore experienced.y l-lereattention is also directed to the fact that by the internal longitudinal flutes in the endportion G of the section 5, it is made possiblefor mud fluid or Water, but more particularly mud fluid, to pass freely up'throu-gh the core barrel around the core in the desired manner, the internal flutes providing; ample clearance therefor. Moreover, through extending certain of the' iin-tes through the larger ec.- centricbore 8, itl Will also be' observed that ample clearance isl providedv through the length of the Vsection 5.

In Fig- 3 I' have illustrateda modified construction which, While-.not preferred or ordinarily necessary, may beusedi if desired, either alone or in conjunction with one or-more shoulders or: ledges further 4up inI theccrebarrel.l In thisl construction it Will beobserved that aneccentric portion 13 is provided 1in. the bit 2 beloiv the core lift-er lland'adapted'to function in essentiallyrthe same manner as the construction .previously described, it being evident that if desired theI bit may be lengthened as necessary to providev the core ivithlthewrequisite access tothe eccentrically disposed ledge orfshnulder 14.

Asa result of my. improvement, it will be observed that an effective core holding means'is provided whereby through the core being caught-by a shoulder o1: ledge or a plurality of the same, the'iveightiisnetted tnally removed from the split ring core lifter in such .manner asy to enable the latter to gripandhold its then. shorter: and

lighter sectionoffcore'evenifi-it is slightly AS a;

smaller than the usual diameter, and there by enable the entire core under average circumstances to belifted from thehole irrespective. of. its weightv orf: variatiansJ in diameter, all in such manner as to enable largerf cores to be removed than it` has heretofore beenthought possible to remove and accordingly to enable the field of use of core drills to be expanded, this expansion being especially marked in the oil well drilling field.' It: slrfnrld,` however, be understood that my invention is not limited to use in connection with large cores orto use inthe oilwell drilling field, it instead-being' obvious that the saine may bensed irres ective of the sizeY ofthecoreorthe/type otdrill: lngV Wherever for anyv reason the-ordinary core" lifter forms an ineffective coreholding means.` These and other advantages of my improvedmonstruction will, however, be clearly apparent to lthose skilled' in ther art-a lhile I have infthis applicaticnspecifi# cally shoWne-nd describedtwo forms which my invention may assume -in practice, it Will be understood that these forms. are shown for purposesof lillnstrationand that the invention may be meditied"and!einbiod'-y ied in various other formsl Without departs ing from itsl spiritiy or the scope. of the-appended claims.

Whaty I. claim as new anddesire to secure by Lette-rs Patent is l; Av core. barrelfhavingra corevreceiving passage, andv oppositely disposedv eccentrically formedstatienarycoreholdingu means spaced lon-gitudinallyofthe barrel adjacent the' core passage'.

2. A core barrel-having aflcore-v receiving passage, and oppositely-Y disposed eccentrically `formed' core holding meansspaded longitudinallyof theMba-rrel and' disposed outside O-the core passage.

3. A core barrel having coreliftingimeans and a central core-passage, and-a plurality of supplemental core holding-means rotatable with the barrel and disposed in longitudi-nally spaced staggered relation 1 outside of said core passage.

4f A` core -barrelhavingfa core receiving passage, core lifting means, and supplemental core holding: means comprising a plurality of oppositely disposedcoref en aging ledges spaced longitudnallyioitfthe arrel and formed out-side. of-x said passager,

5. A core barrel-.havingcoreflifting'meaus and a centrall core passage, and supplemental corel holding means comprising "ai plurality 7. A core barrel having a core receiving passage of substantially the same diameter throughout its length, core lifting means, and supplemental oppositely disposed stationary core holding means formed outside of said passage intermediate its ends at points spaced longitudinally of the barrel.

8. A core barrel having a core receiving passage, core lifting means, and supple mental oppositely disposed stationary baffle means spaced longitudinally of the barrel and formed outside of said passage and engageable by a core when slipping through said lifting means.

9. A core barrel having core lifting means, and supplemental oppositely disposed eccentrically formed stationary core holding means spaced longitudinally of the barrel and engageable by the core upon failure of said lifting means.

10. A core barrel having core lifting means, a core receiving passage, and means rotatable relatively to said lifting means and formed outside and at opposite sides of said passage intermediate its ends at points spaced longitudinally of the barrel and auto matically operative to reduce the weight of the core on said lifting means.

11. A core barrel having core lifting means and a central core passage, and a pair of longitudinally spaced core engaging shoulders oppositely disposed with respect to the core passage and formed wholly outside the latter.

12. A core barrel having core lifting means, and a plurality of passages above the core lifting means eccentric to the core passage and larger than the latter said passages terminating at their lower ends at points spaced longitudinally of the barrel and presenting core engaging shoulders 0n opposite sides thereof.

13. A core barrel comprising a bit, a core lifter, and means above the latter presenting a core passage of substantially the same internal diameter as the bit and communicating eccentrically and oppositely located larger passages presenting core engaging shoulders at points spaced longitudinally of the barrel.

1s. A core barrel comprising a bit, a core lifter, and means above the latter presenting a core passage of substantially the same in-i ternal diameter as the bit and communicating eccentrically and oppositely located larger passages presenting core engaging shoulders at points spaced longitudinally of the barrel and having fluid passages in the walls of both passages.

15.'A core barrel element disposable in a core barrel at a point above the bit and including an external portion having liquid conducting passages therein and an internal core passage likewise having liquid conducting passages therein and including coinmunicating eccentrically and oppositely disposed passages of greater diameter presenting core engaging abutments at point-s spaced longitudinally of the barrel.

16. A core barrel, a resilient core lifter ring normally disposed coaxial therewith and having a conical seat therein, an internally and externally uted bit carried thereon below said core lifter, and means cooperating with the bore through said bit and said lifter and forming a core passage disposed above said lifter and likewise having internal flutes therein, said last mentioned means likewise having therein oppositely disposed bores eccentric with respect to the core passage and forming a part thereof, said bores forming core engaging shoulders at their lower ends at points spaced longitudinally of the barrel.

17. A core cutting bit and a central core barrel having a core receiving passage extending therethrough, and stationary core holding means including a bore disposed eccentrically of said core passage and outside thereof, said bore presenting a core engaging ledge adjacent said core passage.

In testimony whereof I affix my signature. Y

RALPH WILCOX. 

